Alert archive / Texas / Flash Flood Watches in 2021

Flash Flood Watch 4, NWS Shreveport, LA

May 17, 20214 states

NWS Shreveport, LA issued this flash flood watch at May 17, 2021, 1:56 PM CDT for 4 states. It took effect at May 18, 2021, 7:00 AM CDT. It was in force for 4 days.

The area

The counties it named.

The facts

Issued
May 17, 2021, 1:56 PM CDT (18:56 UTC)
In effect from
May 18, 2021, 7:00 AM CDT
Expired
May 22, 2021, 2:50 AM CDT
In force
4 days
Issued by
NWS Shreveport, LA
Flood severity
None
All 43 counties

Columbia County, AR, Hempstead County, AR, Howard County, AR, Lafayette County, AR, Little River County, AR, Miller County, AR, Nevada County, AR, Sevier County, AR, Bienville Parish, LA, Bossier Parish, LA, Caddo Parish, LA, Claiborne Parish, LA, De Soto Parish, LA, Grant Parish, LA, Jackson Parish, LA, Lincoln Parish, LA, Natchitoches Parish, LA, Red River Parish, LA, Sabine Parish, LA, Webster Parish, LA, Winn Parish, LA, McCurtain County, OK, Angelina County, TX, Bowie County, TX, Camp County, TX, Cass County, TX, Cherokee County, TX, Franklin County, TX, Gregg County, TX, Harrison County, TX, Marion County, TX, Morris County, TX, Nacogdoches County, TX, Panola County, TX, Red River County, TX, Rusk County, TX, Sabine County, TX, San Augustine County, TX, Shelby County, TX, Smith County, TX, Titus County, TX, Upshur County, TX, Wood County, TX

The radar

The Shreveport radar (KSHV), 30 km from the middle of the area, began a volume at 18:59 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Shreveport, LA (KSHV), launched 12:00Z, 6.9 hours before the alert went out and 34 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Shreveport, LA at 12:00Z on 2021-05-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 269 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Shreveport, LA at 12:00Z on 2021-05-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 168 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
269 J/kg
Mixed-layer CIN
-26 J/kg
Mixed-layer LCL
462 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
168 m²/s²
0-3 km storm-relative helicity
212 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

886 
WGUS64 KSHV 171856
FFASHV

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Shreveport LA
156 PM CDT Mon May 17 2021

ARZ050-051-059>061-070>072-LAZ001>005-010>013-017>020-OKZ077-TXZ096-
097-108>112-124>126-136>138-149>153-165>167-181900-
/O.NEW.KSHV.FF.A.0004.210518T1200Z-210520T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Sevier-Howard-Little River-Hempstead-Nevada-Miller-Lafayette-
Columbia-Caddo-Bossier-Webster-Claiborne-Lincoln-De Soto-Red River-
Bienville-Jackson-Sabine-Natchitoches-Winn-Grant-McCurtain-Red River-
Bowie-Franklin-Titus-Camp-Morris-Cass-Wood-Upshur-Marion-Smith-Gregg-
Harrison-Cherokee-Rusk-Panola-Nacogdoches-Shelby-Angelina-San
Augustine-Sabine-
Including the cities of Colfax, Hawkins, Ashdown, Center, Carthage, 
Magnolia, Ruston, Gibsland, Winnsboro, Montgomery, Stamps, 
Jefferson, Pleasant Hill, Mineola, Springhill, Naples, Hope, 
Henderson, Linden, Nacogdoches, Bossier City, Broken Bow, Zwolle, 
Hughes Springs, Gilmer, Nashville, San Augustine, Mount Pleasant, 
Lone Star, Lewisville, Mineral Springs, Mansfield, Coushatta, 
Shreveport, Jonesboro, Queen City, Atlanta, Quitman, Mount Vernon, 
Minden, Homer, Rusk, Arcadia, Natchitoches, Omaha, De Queen, 
Pineland, Many, Dry Prong, Stonewall, Clarksville, Martin, Prescott, 
Big Sandy, Ringgold, Texarkana, Daingerfield, Bogata, Pittsburg, 
Marshall, Haynesville, Winnfield, Jacksonville, Bradley, Tyler, 
Logansport, Hemphill, Dierks, Lufkin, Idabel, and Longview
156 PM CDT Mon May 17 2021

...FLASH FLOOD WATCH IN EFFECT FROM TUESDAY MORNING THROUGH THURSDAY 
MORNING...

The National Weather Service in Shreveport has issued a

* Flash Flood Watch for portions of southwest Arkansas...Louisiana...
  southeast Oklahoma and Texas, including the following areas, in 
  southwest Arkansas, Columbia, Hempstead, Howard, Lafayette, Little 
  River, Miller, Nevada and Sevier. In Louisiana, Bienville, 
  Bossier, Caddo, Claiborne, De Soto, Grant, Jackson, Lincoln, 
  Natchitoches, Red River, Sabine, Webster and Winn. In southeast 
  Oklahoma, McCurtain. In Texas, Angelina, Bowie, Camp, Cass, 
  Cherokee, Franklin, Gregg, Harrison, Marion, Morris, Nacogdoches, 
  Panola, Red River, Rusk, Sabine, San Augustine, Shelby, Smith, 
  Titus, Upshur and Wood.

* From Tuesday morning through Thursday morning

* Rainfall totals of 2 to 6 inches with isolated higher amounts 
  possible.

* Flooding may occur in urban and poor drainage areas.  Heavy 
  rainfall may also cause flooding of creeks, streams, and rivers.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead to 
Flash Flooding. Flash Flooding is a very dangerous situation. You 
should monitor later forecasts and be prepared to take action should 
Flash Flood Warnings be issued.

&&

$$

19
11 follow-up statements
718 
WGUS64 KSHV 180903
FFASHV

Flood Watch
National Weather Service Shreveport LA
403 AM CDT Tue May 18 2021

ARZ050-051-059>061-070>072-LAZ001>005-010>013-017>020-OKZ077-
TXZ096-097-108>112-124>126-136>138-149>153-165>167-181715-
/O.CON.KSHV.FF.A.0004.210518T1200Z-210520T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Sevier-Howard-Little River-Hempstead-Nevada-Miller-Lafayette-
Columbia-Caddo-Bossier-Webster-Claiborne-Lincoln-De Soto-
Red River-Bienville-Jackson-Sabine-Natchitoches-Winn-Grant-
McCurtain-Bowie-Franklin-Titus-Camp-Morris-Cass-Wood-Upshur-
Marion-Smith-Gregg-Harrison-Cherokee-Rusk-Panola-Nacogdoches-
Shelby-Angelina-San Augustine-
Including the cities of De Queen, Nashville, Mineral Springs, 
Dierks, Ashdown, Hope, Prescott, Texarkana, Stamps, Lewisville, 
Bradley, Magnolia, Shreveport, Bossier City, Minden, Springhill, 
Homer, Haynesville, Ruston, Mansfield, Stonewall, Logansport, 
Coushatta, Martin, Arcadia, Ringgold, Gibsland, Jonesboro, Many, 
Zwolle, Pleasant Hill, Natchitoches, Winnfield, Colfax, 
Montgomery, Dry Prong, Idabel, Broken Bow, Clarksville, Bogata, 
Mount Vernon, Mount Pleasant, Pittsburg, Daingerfield, Lone Star,
Naples, Omaha, Atlanta, Linden, Hughes Springs, Queen City, 
Mineola, Winnsboro, Quitman, Hawkins, Gilmer, Big Sandy, 
Jefferson, Tyler, Longview, Marshall, Jacksonville, Rusk, 
Henderson, Carthage, Nacogdoches, Center, Lufkin, San Augustine, 
Hemphill, and Pineland
403 AM CDT Tue May 18 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT FROM 7 AM CDT THIS MORNING
THROUGH THURSDAY MORNING...

The Flash Flood Watch continues for

* Portions of southwest Arkansas, Louisiana, southeast Oklahoma, 
  and Texas, including the following areas, in southwest 
  Arkansas, Columbia, Hempstead, Howard, Lafayette, Little 
  River, Miller, Nevada, and Sevier. In Louisiana, Bienville, 
  Bossier, Caddo, Claiborne, De Soto, Grant, Jackson, Lincoln, 
  Natchitoches, Red River, Sabine, Webster, and Winn. In 
  southeast Oklahoma, McCurtain. In Texas, Angelina, Bowie, 
  Camp, Cass, Cherokee, Franklin, Gregg, Harrison, Marion, 
  Morris, Nacogdoches, Panola, Red River, Rusk, Sabine, San 
  Augustine, Shelby, Smith, Titus, Upshur, and Wood. 

* From 7 AM CDT this morning through Thursday morning

* Additional rainfall totals of 2 to 5 inches with isolated higher
  amounts in excess of 6 inches possible. 

* Flooding may occur in urban and poor drainage areas. Heavy 
  rainfall may also cause flooding of creeks, streams, and 
  rivers. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead
to Flash Flooding. Flash Flooding is a very dangerous situation.
You should monitor later forecasts and be prepared to take action
should Flash Flood Warnings be issued.

&&

$$

33
978 
WGUS64 KSHV 182041
FFASHV

Flood Watch
National Weather Service Shreveport LA
341 PM CDT Tue May 18 2021

ARZ050-051-059>061-070>072-LAZ001>005-010>013-017>020-OKZ077-TXZ096-
097-108>112-124>126-136>138-149>153-165>167-191200-
/O.CON.KSHV.FF.A.0004.000000T0000Z-210520T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Sevier-Howard-Little River-Hempstead-Nevada-Miller-Lafayette-
Columbia-Caddo-Bossier-Webster-Claiborne-Lincoln-De Soto-Red River-
Bienville-Jackson-Sabine-Natchitoches-Winn-Grant-McCurtain-Red River-
Bowie-Franklin-Titus-Camp-Morris-Cass-Wood-Upshur-Marion-Smith-Gregg-
Harrison-Cherokee-Rusk-Panola-Nacogdoches-Shelby-Angelina-San
Augustine-Sabine-
Including the cities of Colfax, Hawkins, Ashdown, Center, Carthage, 
Magnolia, Ruston, Gibsland, Winnsboro, Montgomery, Stamps, 
Jefferson, Pleasant Hill, Mineola, Springhill, Naples, Hope, 
Henderson, Linden, Nacogdoches, Bossier City, Broken Bow, Zwolle, 
Hughes Springs, Gilmer, Nashville, San Augustine, Mount Pleasant, 
Lone Star, Lewisville, Mineral Springs, Mansfield, Coushatta, 
Shreveport, Jonesboro, Queen City, Atlanta, Quitman, Mount Vernon, 
Minden, Homer, Rusk, Arcadia, Natchitoches, Omaha, De Queen, 
Pineland, Many, Dry Prong, Stonewall, Clarksville, Martin, Prescott, 
Big Sandy, Ringgold, Texarkana, Daingerfield, Bogata, Pittsburg, 
Marshall, Haynesville, Winnfield, Jacksonville, Bradley, Tyler, 
Logansport, Hemphill, Dierks, Lufkin, Idabel, and Longview
341 PM CDT Tue May 18 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH THURSDAY MORNING...

The Flash Flood Watch continues for

* Portions of southwest Arkansas...Louisiana...southeast Oklahoma 
  and Texas, including the following areas, in southwest Arkansas, 
  Columbia, Hempstead, Howard, Lafayette, Little River, Miller, 
  Nevada and Sevier. In Louisiana, Bienville, Bossier, Caddo, 
  Claiborne, De Soto, Grant, Jackson, Lincoln, Natchitoches, Red 
  River, Sabine, Webster and Winn. In southeast Oklahoma, McCurtain. 
  In Texas, Angelina, Bowie, Camp, Cass, Cherokee, Franklin, Gregg, 
  Harrison, Marion, Morris, Nacogdoches, Panola, Red River, Rusk, 
  Sabine, San Augustine, Shelby, Smith, Titus, Upshur and Wood.

* Through Thursday morning

* Additional rainfall totals of 2 to 5 inches with isolated higher 
  amounts in excess of 6 inches possible.

* Flooding may occur in urban and poor drainage areas.  Heavy 
  rainfall may also cause flooding of creeks, streams, and rivers.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead to 
Flash Flooding. Flash Flooding is a very dangerous situation. You 
should monitor later forecasts and be prepared to take action should 
Flash Flood Warnings be issued.

&&

$$

20
214 
WGUS64 KSHV 190921
FFASHV

Flood Watch
National Weather Service Shreveport LA
421 AM CDT Wed May 19 2021

ARZ050-051-059>061-070>072-LAZ001>005-010>013-017>020-OKZ077-
TXZ096-097-108>112-124>126-136>138-149>153-165>167-191730-
/O.CON.KSHV.FF.A.0004.000000T0000Z-210520T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Sevier-Howard-Little River-Hempstead-Nevada-Miller-Lafayette-
Columbia-Caddo-Bossier-Webster-Claiborne-Lincoln-De Soto-
Red River-Bienville-Jackson-Sabine-Natchitoches-Winn-Grant-
McCurtain-Bowie-Franklin-Titus-Camp-Morris-Cass-Wood-Upshur-
Marion-Smith-Gregg-Harrison-Cherokee-Rusk-Panola-Nacogdoches-
Shelby-Angelina-San Augustine-
Including the cities of De Queen, Nashville, Mineral Springs, 
Dierks, Ashdown, Hope, Prescott, Texarkana, Stamps, Lewisville, 
Bradley, Magnolia, Shreveport, Bossier City, Minden, Springhill, 
Homer, Haynesville, Ruston, Mansfield, Stonewall, Logansport, 
Coushatta, Martin, Arcadia, Ringgold, Gibsland, Jonesboro, Many, 
Zwolle, Pleasant Hill, Natchitoches, Winnfield, Colfax, 
Montgomery, Dry Prong, Idabel, Broken Bow, Clarksville, Bogata, 
Mount Vernon, Mount Pleasant, Pittsburg, Daingerfield, Lone Star,
Naples, Omaha, Atlanta, Linden, Hughes Springs, Queen City, 
Mineola, Winnsboro, Quitman, Hawkins, Gilmer, Big Sandy, 
Jefferson, Tyler, Longview, Marshall, Jacksonville, Rusk, 
Henderson, Carthage, Nacogdoches, Center, Lufkin, San Augustine, 
Hemphill, and Pineland
421 AM CDT Wed May 19 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH THURSDAY MORNING...

The Flash Flood Watch continues for

* Portions of southwest Arkansas, Louisiana, southeast Oklahoma, 
  and Texas, including the following areas, in southwest 
  Arkansas, Columbia, Hempstead, Howard, Lafayette, Little 
  River, Miller, Nevada, and Sevier. In Louisiana, Bienville, 
  Bossier, Caddo, Claiborne, De Soto, Grant, Jackson, Lincoln, 
  Natchitoches, Red River, Sabine, Webster, and Winn. In 
  southeast Oklahoma, McCurtain. In Texas, Angelina, Bowie, 
  Camp, Cass, Cherokee, Franklin, Gregg, Harrison, Marion, 
  Morris, Nacogdoches, Panola, Red River, Rusk, Sabine, San 
  Augustine, Shelby, Smith, Titus, Upshur, and Wood. 

* Through Thursday morning

* Additional rainfall totals of 1 to 2 inches with isolated higher
  amounts of 3 inches or more possible. 

* Flooding may occur in urban and poor drainage areas. Heavy 
  rainfall may also cause flooding of creeks, streams, and 
  rivers. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead
to Flash Flooding. Flash Flooding is a very dangerous situation.
You should monitor later forecasts and be prepared to take action
should Flash Flood Warnings be issued.

&&

$$

33
584 
WGUS64 KSHV 191932
FFASHV

Flood Watch
National Weather Service Shreveport LA
232 PM CDT Wed May 19 2021

ARZ050-051-059>061-070>072-LAZ001>005-010>013-017>020-OKZ077-TXZ096-
097-108>112-124>126-136>138-149>153-165>167-201200-
/O.CON.KSHV.FF.A.0004.000000T0000Z-210520T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Sevier-Howard-Little River-Hempstead-Nevada-Miller-Lafayette-
Columbia-Caddo-Bossier-Webster-Claiborne-Lincoln-De Soto-Red River-
Bienville-Jackson-Sabine-Natchitoches-Winn-Grant-McCurtain-Red River-
Bowie-Franklin-Titus-Camp-Morris-Cass-Wood-Upshur-Marion-Smith-Gregg-
Harrison-Cherokee-Rusk-Panola-Nacogdoches-Shelby-Angelina-San
Augustine-Sabine-
Including the cities of Colfax, Hawkins, Ashdown, Center, Carthage, 
Magnolia, Ruston, Gibsland, Winnsboro, Montgomery, Stamps, 
Jefferson, Pleasant Hill, Mineola, Springhill, Naples, Hope, 
Henderson, Linden, Nacogdoches, Bossier City, Broken Bow, Zwolle, 
Hughes Springs, Gilmer, Nashville, San Augustine, Mount Pleasant, 
Lone Star, Lewisville, Mineral Springs, Mansfield, Coushatta, 
Shreveport, Jonesboro, Queen City, Atlanta, Quitman, Mount Vernon, 
Minden, Homer, Rusk, Arcadia, Natchitoches, Omaha, De Queen, 
Pineland, Many, Dry Prong, Stonewall, Clarksville, Martin, Prescott, 
Big Sandy, Ringgold, Texarkana, Daingerfield, Bogata, Pittsburg, 
Marshall, Haynesville, Winnfield, Jacksonville, Bradley, Tyler, 
Logansport, Hemphill, Dierks, Lufkin, Idabel, and Longview
232 PM CDT Wed May 19 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH THURSDAY MORNING...

The Flash Flood Watch continues for

* Portions of southwest Arkansas...Louisiana...southeast Oklahoma 
  and Texas, including the following areas, in southwest Arkansas, 
  Columbia, Hempstead, Howard, Lafayette, Little River, Miller, 
  Nevada and Sevier. In Louisiana, Bienville, Bossier, Caddo, 
  Claiborne, De Soto, Grant, Jackson, Lincoln, Natchitoches, Red 
  River, Sabine, Webster and Winn. In southeast Oklahoma, McCurtain. 
  In Texas, Angelina, Bowie, Camp, Cass, Cherokee, Franklin, Gregg, 
  Harrison, Marion, Morris, Nacogdoches, Panola, Red River, Rusk, 
  Sabine, San Augustine, Shelby, Smith, Titus, Upshur and Wood.

* Through Thursday morning

* Additional rainfall totals of 1 to 2 inches, with isolated higher 
  amounts of 3 inches or more possible.

* Flooding may occur in urban and poor drainage areas.  Heavy 
  rainfall may also cause flooding of creeks, streams, and rivers.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead to 
Flash Flooding. Flash Flooding is a very dangerous situation. You 
should monitor later forecasts and be prepared to take action should 
Flash Flood Warnings be issued.

&&

$$
388 
WGUS64 KSHV 200804
FFASHV

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Shreveport LA
304 AM CDT Thu May 20 2021

ARZ050-051-059>061-070>072-LAZ001>005-010>013-017>020-OKZ077-TXZ096-
097-108>112-124>126-136>138-149>153-165>167-201615-
/O.EXT.KSHV.FF.A.0004.000000T0000Z-210521T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Sevier-Howard-Little River-Hempstead-Nevada-Miller-Lafayette-
Columbia-Caddo-Bossier-Webster-Claiborne-Lincoln-De Soto-Red River-
Bienville-Jackson-Sabine-Natchitoches-Winn-Grant-McCurtain-Red River-
Bowie-Franklin-Titus-Camp-Morris-Cass-Wood-Upshur-Marion-Smith-Gregg-
Harrison-Cherokee-Rusk-Panola-Nacogdoches-Shelby-Angelina-San
Augustine-Sabine-
Including the cities of Colfax, Hawkins, Ashdown, Center, Carthage, 
Magnolia, Ruston, Gibsland, Winnsboro, Montgomery, Stamps, 
Jefferson, Pleasant Hill, Mineola, Springhill, Naples, Hope, 
Henderson, Linden, Nacogdoches, Bossier City, Broken Bow, Zwolle, 
Hughes Springs, Gilmer, Nashville, San Augustine, Mount Pleasant, 
Lone Star, Lewisville, Mineral Springs, Mansfield, Coushatta, 
Shreveport, Jonesboro, Queen City, Atlanta, Quitman, Mount Vernon, 
Minden, Homer, Rusk, Arcadia, Natchitoches, Omaha, De Queen, 
Pineland, Many, Dry Prong, Stonewall, Clarksville, Martin, Prescott, 
Big Sandy, Ringgold, Texarkana, Daingerfield, Bogata, Pittsburg, 
Marshall, Haynesville, Winnfield, Jacksonville, Bradley, Tyler, 
Logansport, Hemphill, Dierks, Lufkin, Idabel, and Longview
304 AM CDT Thu May 20 2021

...FLASH FLOOD WATCH NOW IN EFFECT THROUGH THIS EVENING...

The Flash Flood Watch is now in effect for

* Portions of southwest Arkansas...Louisiana...southeast Oklahoma 
  and Texas, including the following areas, in southwest Arkansas, 
  Columbia, Hempstead, Howard, Lafayette, Little River, Miller, 
  Nevada and Sevier. In Louisiana, Bienville, Bossier, Caddo, 
  Claiborne, De Soto, Grant, Jackson, Lincoln, Natchitoches, Red 
  River, Sabine, Webster and Winn. In southeast Oklahoma, McCurtain. 
  In Texas, Angelina, Bowie, Camp, Cass, Cherokee, Franklin, Gregg, 
  Harrison, Marion, Morris, Nacogdoches, Panola, Red River, Rusk, 
  Sabine, San Augustine, Shelby, Smith, Titus, Upshur and Wood.

* Through this evening

* Rainfall totals of 1 to 2 inches, with isolated locally higher 
  amounts possible.

* Flooding may occur in urban and poor drainage areas.  Heavy 
  rainfall may also cause flooding of creeks, streams, and rivers.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead to 
Flash Flooding. Flash Flooding is a very dangerous situation. You 
should monitor later forecasts and be prepared to take action should 
Flash Flood Warnings be issued.

&&

$$

33
328 
WGUS64 KSHV 201842
FFASHV

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Shreveport LA
142 PM CDT Thu May 20 2021

ARZ050-051-059>061-070>072-LAZ001>005-010>013-017>020-OKZ077-
TXZ096-097-108>112-124>126-136>138-149>153-165>167-210245-
/O.EXT.KSHV.FF.A.0004.000000T0000Z-210521T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Sevier-Howard-Little River-Hempstead-Nevada-Miller-Lafayette-
Columbia-Caddo-Bossier-Webster-Claiborne-Lincoln-De Soto-
Red River-Bienville-Jackson-Sabine-Natchitoches-Winn-Grant-
McCurtain-Bowie-Franklin-Titus-Camp-Morris-Cass-Wood-Upshur-
Marion-Smith-Gregg-Harrison-Cherokee-Rusk-Panola-Nacogdoches-
Shelby-Angelina-San Augustine-
Including the cities of De Queen, Nashville, Mineral Springs, 
Dierks, Ashdown, Hope, Prescott, Texarkana, Stamps, Lewisville, 
Bradley, Magnolia, Shreveport, Bossier City, Minden, Springhill, 
Homer, Haynesville, Ruston, Mansfield, Stonewall, Logansport, 
Coushatta, Martin, Arcadia, Ringgold, Gibsland, Jonesboro, Many, 
Zwolle, Pleasant Hill, Natchitoches, Winnfield, Colfax, 
Montgomery, Dry Prong, Idabel, Broken Bow, Clarksville, Bogata, 
Mount Vernon, Mount Pleasant, Pittsburg, Daingerfield, Lone Star,
Naples, Omaha, Atlanta, Linden, Hughes Springs, Queen City, 
Mineola, Winnsboro, Quitman, Hawkins, Gilmer, Big Sandy, 
Jefferson, Tyler, Longview, Marshall, Jacksonville, Rusk, 
Henderson, Carthage, Nacogdoches, Center, Lufkin, San Augustine, 
Hemphill, and Pineland
142 PM CDT Thu May 20 2021

...FLASH FLOOD WATCH NOW IN EFFECT UNTIL 1 AM CDT FRIDAY...

The Flash Flood Watch is now in effect for

* Portions of southwest Arkansas, Louisiana, southeast Oklahoma, 
  and Texas, including the following areas, in southwest 
  Arkansas, Columbia, Hempstead, Howard, Lafayette, Little 
  River, Miller, Nevada, and Sevier. In Louisiana, Bienville, 
  Bossier, Caddo, Claiborne, De Soto, Grant, Jackson, Lincoln, 
  Natchitoches, Red River, Sabine, Webster, and Winn. In 
  southeast Oklahoma, McCurtain. In Texas, Angelina, Bowie, 
  Camp, Cass, Cherokee, Franklin, Gregg, Harrison, Marion, 
  Morris, Nacogdoches, Panola, Red River, Rusk, Sabine, San 
  Augustine, Shelby, Smith, Titus, Upshur, and Wood. 

* Until 1 AM CDT Friday

* Rainfall totals of 1 to 2 inches, with isolated locally higher 
  amounts possible. 

* Flooding may occur in urban and poor drainage areas. Heavy 
  rainfall may also cause flooding of creeks, streams, and 
  rivers. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead
to Flash Flooding. Flash Flooding is a very dangerous situation.
You should monitor later forecasts and be prepared to take action
should Flash Flood Warnings be issued.

&&

$$

50
291 
WGUS64 KSHV 210236
FFASHV

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Shreveport LA
936 PM CDT Thu May 20 2021

ARZ050-051-059>061-070>072-LAZ001>005-010>013-017>020-OKZ077-TXZ096-
097-108>112-124>126-136>138-149>153-165>167-211045-
/O.EXT.KSHV.FF.A.0004.000000T0000Z-210521T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Sevier-Howard-Little River-Hempstead-Nevada-Miller-Lafayette-
Columbia-Caddo-Bossier-Webster-Claiborne-Lincoln-De Soto-Red River-
Bienville-Jackson-Sabine-Natchitoches-Winn-Grant-McCurtain-Red River-
Bowie-Franklin-Titus-Camp-Morris-Cass-Wood-Upshur-Marion-Smith-Gregg-
Harrison-Cherokee-Rusk-Panola-Nacogdoches-Shelby-Angelina-San
Augustine-Sabine-
Including the cities of Colfax, Hawkins, Ashdown, Center, Carthage, 
Magnolia, Ruston, Gibsland, Winnsboro, Montgomery, Stamps, 
Jefferson, Pleasant Hill, Mineola, Springhill, Naples, Hope, 
Henderson, Linden, Nacogdoches, Bossier City, Broken Bow, Zwolle, 
Hughes Springs, Gilmer, Nashville, San Augustine, Mount Pleasant, 
Lone Star, Lewisville, Mineral Springs, Mansfield, Coushatta, 
Shreveport, Jonesboro, Queen City, Atlanta, Quitman, Mount Vernon, 
Minden, Homer, Rusk, Arcadia, Natchitoches, Omaha, De Queen, 
Pineland, Many, Dry Prong, Stonewall, Clarksville, Martin, Prescott, 
Big Sandy, Ringgold, Texarkana, Daingerfield, Bogata, Pittsburg, 
Marshall, Haynesville, Winnfield, Jacksonville, Bradley, Tyler, 
Logansport, Hemphill, Dierks, Lufkin, Idabel, and Longview
936 PM CDT Thu May 20 2021

...FLASH FLOOD WATCH NOW IN EFFECT UNTIL 7 AM CDT FRIDAY...

The Flash Flood Watch is now in effect for

* Portions of southwest Arkansas...Louisiana...southeast Oklahoma 
  and Texas, including the following areas, in southwest Arkansas, 
  Columbia, Hempstead, Howard, Lafayette, Little River, Miller, 
  Nevada and Sevier. In Louisiana, Bienville, Bossier, Caddo, 
  Claiborne, De Soto, Grant, Jackson, Lincoln, Natchitoches, Red 
  River, Sabine, Webster and Winn. In southeast Oklahoma, McCurtain. 
  In Texas, Angelina, Bowie, Camp, Cass, Cherokee, Franklin, Gregg, 
  Harrison, Marion, Morris, Nacogdoches, Panola, Red River, Rusk, 
  Sabine, San Augustine, Shelby, Smith, Titus, Upshur and Wood.

* Until 7 AM CDT Friday

* Rainfall totals of 1 to 3 inches, with isolated higher amounts 
  possible.

* Flooding may occur in urban and poor drainage areas.  Heavy 
  rainfall may also cause flooding of creeks, streams, and rivers.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead to 
Flash Flooding. Flash Flooding is a very dangerous situation. You 
should monitor later forecasts and be prepared to take action should 
Flash Flood Warnings be issued.

&&

$$

24
541 
WGUS64 KSHV 210750
FFASHV

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Shreveport LA
250 AM CDT Fri May 21 2021

ARZ050-051-059>061-070>072-LAZ001>005-010>013-017>020-OKZ077-TXZ096-
097-108>112-124>126-136>138-149>153-165>167-220000-
/O.EXT.KSHV.FF.A.0004.000000T0000Z-210522T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Sevier-Howard-Little River-Hempstead-Nevada-Miller-Lafayette-
Columbia-Caddo-Bossier-Webster-Claiborne-Lincoln-De Soto-Red River-
Bienville-Jackson-Sabine-Natchitoches-Winn-Grant-McCurtain-Red River-
Bowie-Franklin-Titus-Camp-Morris-Cass-Wood-Upshur-Marion-Smith-Gregg-
Harrison-Cherokee-Rusk-Panola-Nacogdoches-Shelby-Angelina-San
Augustine-Sabine-
Including the cities of Colfax, Hawkins, Ashdown, Center, Carthage, 
Magnolia, Ruston, Gibsland, Winnsboro, Montgomery, Stamps, 
Jefferson, Pleasant Hill, Mineola, Springhill, Naples, Hope, 
Henderson, Linden, Nacogdoches, Bossier City, Broken Bow, Zwolle, 
Hughes Springs, Gilmer, Nashville, San Augustine, Mount Pleasant, 
Lone Star, Lewisville, Mineral Springs, Mansfield, Coushatta, 
Shreveport, Jonesboro, Queen City, Atlanta, Quitman, Mount Vernon, 
Minden, Homer, Rusk, Arcadia, Natchitoches, Omaha, De Queen, 
Pineland, Many, Dry Prong, Stonewall, Clarksville, Martin, Prescott, 
Big Sandy, Ringgold, Texarkana, Daingerfield, Bogata, Pittsburg, 
Marshall, Haynesville, Winnfield, Jacksonville, Bradley, Tyler, 
Logansport, Hemphill, Dierks, Lufkin, Idabel, and Longview
250 AM CDT Fri May 21 2021

...FLASH FLOOD WATCH NOW IN EFFECT THROUGH THIS EVENING...

The Flash Flood Watch is now in effect for

* Portions of southwest Arkansas...Louisiana...southeast Oklahoma 
  and Texas, including the following areas, in southwest Arkansas, 
  Columbia, Hempstead, Howard, Lafayette, Little River, Miller, 
  Nevada and Sevier. In Louisiana, Bienville, Bossier, Caddo, 
  Claiborne, De Soto, Grant, Jackson, Lincoln, Natchitoches, Red 
  River, Sabine, Webster and Winn. In southeast Oklahoma, McCurtain. 
  In Texas, Angelina, Bowie, Camp, Cass, Cherokee, Franklin, Gregg, 
  Harrison, Marion, Morris, Nacogdoches, Panola, Red River, Rusk, 
  Sabine, San Augustine, Shelby, Smith, Titus, Upshur and Wood.

* Through this evening

* Rainfall totals of 1 to 3 inches, with isolated higher amounts 
  possible.

* Flooding may occur in urban and poor drainage areas.  Heavy 
  rainfall may also cause flooding of creeks, streams, and rivers.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead to 
Flash Flooding. Flash Flooding is a very dangerous situation. You 
should monitor later forecasts and be prepared to take action should 
Flash Flood Warnings be issued.

&&

$$

16
019 
WGUS64 KSHV 211950
FFASHV

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Shreveport LA
250 PM CDT Fri May 21 2021

ARZ050-051-059>061-070>072-LAZ001>005-010>013-017>020-OKZ077-TXZ096-
097-108>112-124>126-136>138-149>153-165>167-220400-
/O.EXT.KSHV.FF.A.0004.000000T0000Z-210522T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Sevier-Howard-Little River-Hempstead-Nevada-Miller-Lafayette-
Columbia-Caddo-Bossier-Webster-Claiborne-Lincoln-De Soto-Red River-
Bienville-Jackson-Sabine-Natchitoches-Winn-Grant-McCurtain-Red River-
Bowie-Franklin-Titus-Camp-Morris-Cass-Wood-Upshur-Marion-Smith-Gregg-
Harrison-Cherokee-Rusk-Panola-Nacogdoches-Shelby-Angelina-San
Augustine-Sabine-
Including the cities of Colfax, Hawkins, Ashdown, Center, Carthage, 
Magnolia, Ruston, Gibsland, Winnsboro, Montgomery, Stamps, 
Jefferson, Pleasant Hill, Mineola, Springhill, Naples, Hope, 
Henderson, Linden, Nacogdoches, Bossier City, Broken Bow, Zwolle, 
Hughes Springs, Gilmer, Nashville, San Augustine, Mount Pleasant, 
Lone Star, Lewisville, Mineral Springs, Mansfield, Coushatta, 
Shreveport, Jonesboro, Queen City, Atlanta, Quitman, Mount Vernon, 
Minden, Homer, Rusk, Arcadia, Natchitoches, Omaha, De Queen, 
Pineland, Many, Dry Prong, Stonewall, Clarksville, Martin, Prescott, 
Big Sandy, Ringgold, Texarkana, Daingerfield, Bogata, Pittsburg, 
Marshall, Haynesville, Winnfield, Jacksonville, Bradley, Tyler, 
Logansport, Hemphill, Dierks, Lufkin, Idabel, and Longview
250 PM CDT Fri May 21 2021

...FLASH FLOOD WATCH NOW IN EFFECT THROUGH SATURDAY MORNING...

The Flash Flood Watch is now in effect for

* Portions of southwest Arkansas...Louisiana...southeast Oklahoma 
  and Texas, including the following areas, in southwest Arkansas, 
  Columbia, Hempstead, Howard, Lafayette, Little River, Miller, 
  Nevada and Sevier. In Louisiana, Bienville, Bossier, Caddo, 
  Claiborne, De Soto, Grant, Jackson, Lincoln, Natchitoches, Red 
  River, Sabine, Webster and Winn. In southeast Oklahoma, McCurtain. 
  In Texas, Angelina, Bowie, Camp, Cass, Cherokee, Franklin, Gregg, 
  Harrison, Marion, Morris, Nacogdoches, Panola, Red River, Rusk, 
  Sabine, San Augustine, Shelby, Smith, Titus, Upshur and Wood.

* Through Saturday morning

* Additional rainfall totals of 1 to 2 inches, with isolated higher 
  amounts possible.

* Flooding may occur in urban and poor drainage areas.  Heavy 
  rainfall may also cause flooding of creeks, streams, and rivers.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead to 
Flash Flooding. Flash Flooding is a very dangerous situation. You 
should monitor later forecasts and be prepared to take action should 
Flash Flood Warnings be issued.

&&

$$

20
038 
WGUS64 KSHV 220233
FFASHV

Flood Watch
National Weather Service Shreveport LA
933 PM CDT Fri May 21 2021

ARZ050-051-059>061-070>072-LAZ001>005-010>013-018>020-220345-
/O.CAN.KSHV.FF.A.0004.000000T0000Z-210522T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Sevier-Howard-Little River-Hempstead-Nevada-Miller-Lafayette-
Columbia-Caddo-Bossier-Webster-Claiborne-Lincoln-De Soto-Red River-
Bienville-Jackson-Natchitoches-Winn-Grant-
Including the cities of Colfax, Ashdown, Magnolia, Ruston, Gibsland, 
Montgomery, Stamps, Springhill, Hope, Bossier City, Nashville, 
Lewisville, Mineral Springs, Mansfield, Coushatta, Shreveport, 
Jonesboro, Minden, Homer, Arcadia, Natchitoches, De Queen, Dry 
Prong, Stonewall, Martin, Prescott, Ringgold, Texarkana, 
Haynesville, Winnfield, Bradley, Logansport, and Dierks
933 PM CDT Fri May 21 2021

...FLASH FLOOD WATCH IS CANCELLED...

The Flash Flood Watch for portions of southwest Arkansas and 
Louisiana, including the following areas, in southwest Arkansas, 
Columbia, Hempstead, Howard, Lafayette, Little River, Miller, Nevada 
and Sevier. In Louisiana, Bienville, Bossier, Caddo, Claiborne, De 
Soto, Grant, Jackson, Lincoln, Natchitoches, Red River, Webster and 
Winn has been cancelled.

Flooding is no longer expected to pose a threat. Please continue to 
heed remaining road closures.

$$

LAZ017-OKZ077-TXZ096-097-108>112-124>126-136>138-149>153-165>167-
221200-
/O.CON.KSHV.FF.A.0004.000000T0000Z-210522T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Sabine-McCurtain-Red River-Bowie-Franklin-Titus-Camp-Morris-Cass-
Wood-Upshur-Marion-Smith-Gregg-Harrison-Cherokee-Rusk-Panola-
Nacogdoches-Shelby-Angelina-San Augustine-Sabine-
Including the cities of Hawkins, Center, Carthage, Mount Pleasant, 
Clarksville, Winnsboro, Jefferson, Pleasant Hill, Mineola, Hughes 
Springs, Naples, Henderson, Linden, Nacogdoches, Broken Bow, 
Daingerfield, Gilmer, Lone Star, Queen City, Atlanta, Quitman, Mount 
Vernon, Idabel, Rusk, Omaha, Zwolle, Many, Pineland, Lufkin, Big 
Sandy, Texarkana, Bogata, Pittsburg, Marshall, Jacksonville, Tyler, 
Hemphill, San Augustine, and Longview
933 PM CDT Fri May 21 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT UNTIL 7 AM CDT SATURDAY...

The Flash Flood Watch continues for

* Portions of northwest Louisiana...southeast Oklahoma and Texas, 
  including the following areas, in northwest Louisiana, Sabine. In 
  southeast Oklahoma, McCurtain. In Texas, Angelina, Bowie, Camp, 
  Cass, Cherokee, Franklin, Gregg, Harrison, Marion, Morris, 
  Nacogdoches, Panola, Red River, Rusk, Sabine, San Augustine, 
  Shelby, Smith, Titus, Upshur and Wood.

* Until 7 AM CDT Saturday

* Rainfall totals of 1 to 2 inches, with isolated higher amounts 
  possible.

* Flooding may occur in urban and poor drainage areas.  Heavy 
  rainfall may also cause flooding of creeks, streams, and rivers.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead to 
Flash Flooding. Flash Flooding is a very dangerous situation. You 
should monitor later forecasts and be prepared to take action should 
Flash Flood Warnings be issued.

&&

$$

24
862 
WGUS64 KSHV 220750
FFASHV

Flood Watch
National Weather Service Shreveport LA
250 AM CDT Sat May 22 2021

LAZ017-OKZ077-TXZ096-097-108>112-124>126-136>138-149>153-165>167-
220900-
/O.CAN.KSHV.FF.A.0004.000000T0000Z-210522T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Sabine-McCurtain-Red River-Bowie-Franklin-Titus-Camp-Morris-Cass-
Wood-Upshur-Marion-Smith-Gregg-Harrison-Cherokee-Rusk-Panola-
Nacogdoches-Shelby-Angelina-San Augustine-Sabine-
Including the cities of Hawkins, Center, Carthage, Mount Pleasant, 
Clarksville, Winnsboro, Jefferson, Pleasant Hill, Mineola, Hughes 
Springs, Naples, Henderson, Linden, Nacogdoches, Broken Bow, 
Daingerfield, Gilmer, Lone Star, Queen City, Atlanta, Quitman, Mount 
Vernon, Idabel, Rusk, Omaha, Zwolle, Many, Pineland, Lufkin, Big 
Sandy, Texarkana, Bogata, Pittsburg, Marshall, Jacksonville, Tyler, 
Hemphill, San Augustine, and Longview
250 AM CDT Sat May 22 2021

...FLASH FLOOD WATCH IS CANCELLED...

The Flash Flood Watch for portions of northwest Louisiana...
southeast Oklahoma and Texas, including the following areas, in 
northwest Louisiana, Sabine. In southeast Oklahoma, McCurtain. In 
Texas, Angelina, Bowie, Camp, Cass, Cherokee, Franklin, Gregg, 
Harrison, Marion, Morris, Nacogdoches, Panola, Red River, Rusk, 
Sabine, San Augustine, Shelby, Smith, Titus, Upshur and Wood has 
been cancelled.

Flooding is no longer expected to pose a threat. Please continue to 
heed remaining road closures.

$$

16

What forecasters said that day

The local office's own words before this flash flood watch went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Shreveport, LA wrote its last area forecast discussion before this flash flood watch went out at May 17, 12:51 PM CDT, 1 hour 5 minutes earlier.

Area forecast discussion, May 17, 12:51 PM CDT, 1 hour 5 minutes before
Area Forecast Discussion
National Weather Service Shreveport LA
1251 PM CDT Mon May 17 2021

.AVIATION...

For 17/18Z TAF period, convection continues to gradually spread
east from our East Texas sites into SHV/TXK early this afternoon.
This trend will continue at ELD/MLU by mid to late afternoon as a
weak upper level disturbance shifts farther east across the region
this afternoon. Cigs/vsbys will generally remain in the IFR/MVFR
range through much of the period as low-level moisture continues
to remain abundant. Convection will wane areawide by this evening
and overnight before eventually returning across East Texas by mid
to late morning on Tuesday. Cigs will likely deteriorate further
toward the end of the period with IFR and possibly intermittent
LIFR conditions occurring through Tuesday morning. S/SE winds are
expected to prevail between 5-10 kts with occasional higher gusts.

/19/

&&

.PREV DISCUSSION... /issued 1146 AM CDT Mon May 17 2021/

UPDATE...

Convection continues to spread SE late this morning within an
embedded shortwave across NE Texas. This upper disturbance will
continue to provide the necessary lift and forcing to generate
additional showers and thunderstorms as we move through this
afternoon, especially across the SE half of the region. For the
update this morning, did have to make some adjustments to hourly
and max temperatures to better align with ongoing obs and trends
thus far this morning. In general, this resulted in lowering max
temps by a degree or two in most cases. Otherwise, the remainder
of the forecast is on track. New updated text products have been
issued.

/19/

PREV DISCUSSION... /issued 414 AM CDT Mon May 17 2021/

SHORT TERM.../Today through Tuesday/

Radar imagery from early this morning is showing a few showers
with some embedded thunderstorms across portions of deep east
Texas, extending to the northeast through central Louisiana and
then into northeast Louisiana. Additionally, there are a few
showers moving across southwest Oklahoma as well. Expecting this
activity to continue through the rest of the night and into the
morning hours.

Upper air analysis from this morning shows a well-defined low
centered over the Nevada/Arizona/Utah state lines. Models show
this upper-level low gradually pushing into the Four Corners
Region through the day today. This feature has already sent one of
many rounds of precipitation to the area, which we saw late Sunday
and into last night. Showers and thunderstorms will begin to
increase across the area late this morning and into the early
afternoon hours. While the majority of the severe weather threat
will remain well to our east, there is a chance for marginally
severe thunderstorms generally west of a line from Natchitoches,
LA north to near Prescott, AR were a Marginal Risk is currently
painted for large hail and damaging winds.

At the same time, stronger thunderstorms are expected to develop
across western Texas and slowly move towards our area as we head
into tonight. Showers and thunderstorms will continue to move
through the area tonight and into the day Tuesday. Models indicate
that there could be an ongoing MCS moving across central and north
Texas early Tuesday morning that will track into our area. This
could bring an additional threat of severe weather during the day
Tuesday with all modes of severe weather possible. The area with
the greatest chance of seeing severe weather on Tuesday will be
across portions of east Texas where SPC currently has painted
a Slight Risk.

In addition to the severe weather chances across the area, there
remains a good chance for moderate to heavy rainfall across the
area. While most of the heaviest rain will hold off till later in
the week, a few storms today and Tuesday will produce locally
heavy rainfall. Will likely need a Flash Flood Watch by Tuesday
afternoon, but will hold off and see what the 12z data indicates
for start times. Temperatures today will range from the mid to
upper 70s for areas along and north of I-30 to the lower 80s
elsewhere. Low temperatures tonight will generally range from the
mid to upper 60s. Look for afternoon high temperatures on Tuesday
to range from the upper 70s to lower 80s once again. /33/

LONG TERM.../Tuesday Night through Sunday Night/

The closed low now entering the Desert SW this morning will open up
over the next day or so as it enters the Cntrl/Srn Rockies Tuesday
night, with the attendant upper trough now progged to dig a bit
farther S into NCntrl Old MX. Strong diffluence will set up ahead of
the trough over OK and much of Cntrl TX, with a 30-40kt Srly LLJ
feeding low level moisture Nwd where one or multiple large clusters
of convection will develop by late afternoon/into the evening while
gradually migrating E into ECntrl TX/SE OK/possibly the adjacent
sections of SW AR by daybreak Wednesday. Moderate MLCapes on the
order of 2000-2500 J/Kg is progged to develop within the moist
sector across Ncntrl/Cntrl and NE TX during the late
afternoon/evening Tuesday, such that the developing convection will
pose a svr threat with damaging winds/hail over these areas. This
may translate ENE across the remainder of E TX and possibly Wrn LA
overnight, although instability remains progged to wane during the
late evening/overnight hours with the stabilizing bndry lyr. The
primary threat will then transition to locally heavy rainfall, which
looks to affect much of E TX/SE OK/adjacent sections of SW AR
overnight, which will fall over nearly saturated grounds from heavy
rainfall which fell late last weekend into the early portions of the
week over much of E TX. Timing discrepancies do arise though with
the 00Z progs with the GFS/Canadian/ECMWF a bit more progressive
with the overnight MCS than the slower NAM, although the ECMWF
suggests much lower QPF than earlier runs. Given the strength of the
LLJ and timing consistencies with the majority of the 00Z progs with
the earlier model runs, have not strayed much from the previous
forecasts and have included heavy rain mention Tuesday night over
the aforementioned areas, but did back off on the higher
(likely/categorical) pops until after 06Z Wednesday for the Wrn half
of the area given the potential slower evolution of the developing
MCS. Have maintained likely/categorical pops Wednesday as the MCS
marches E across the region although weakening during the afternoon
as this complex outruns the area of best large scale forcing ahead
of the upper trough to the W. Storm total QPF's through Wednesday
night still looks to range from 3-5+ inches over E TX, SE OK,
adjacent sections of SW AR and possibly Wrn LA, with isolated higher
amounts in excess of 8 inches over portions of E TX.

What's left of the upper level circulation of the trough should
begin to lift N from Ern Co/OK and TX Panhandles into the Cntrl
Plains, with the Srn portions of the residual trough over S TX
progged to dig father S into Ern MX as it becomes pinched off from
the main upper flow. This will come as upper ridging begins to
amplify N from the SE CONUS into the OH Valley/into much of New
England, which will act to shear apart the remainder of the Srn
Plains/Ern MX trough Thursday through next weekend. The convection
Wednesday should begin to gradually wane Wednesday night as the
ridging to the E tries to advect some drier air back to the WNW.
However, a deep SErly unidirectional flow around the Wrn periphery
of the ridge coupled with diurnal heating should result in sct to
numerous areas of convection developing once again areawide, where
likely and categorical pops were maintained, especially across all
but Scntrl AR/Ern sections of NCntrl LA. While this could result in
localized pockets of heavy rain and training, especially over E TX,
the ridge should begin to build a bit farther W through the Lower MS
Valley Friday, thus maintaining more sct convection than the
widespread which will be observed for much of this week.

Disagreements arise with the extent of convection by late week into
next weekend, with the GFS mostly dry during the period, whereas the
ECMWF and to more extent the Canadian suggest more sct mainly
diurnal convection over much of the region. Have remained more
conservative with pops, lowering the much higher NBM pops down to
chance while confining the mid/high chance pops over SE OK/E TX where
the ridging may be weaker. Did lower pops to slight chance across
the Ern zones Saturday given the model consensus, with a warming
trend commencing by late week into the weekend as the ridge nudges
farther W. Decent model agreement exists that by late weekend, any
convection should be more isolated as the ridge retrogrades farther
W into the Lower MS Valley.

15

&&

.PRELIMINARY POINT TEMPS/POPS...
SHV  69  84  68  74 /  40  80  70  90
MLU  68  82  68  81 /  50  80  30  70
DEQ  65  79  65  74 /  60  90  90  90
TXK  68  81  68  74 /  40  80  80  90
ELD  65  82  67  77 /  40  80  50  80
TYR  68  82  66  76 /  40  90  90  90
GGG  67  82  67  75 /  40  90  80  90
LFK  69  83  68  77 /  30  80  70  90

&&

.SHV WATCHES/WARNINGS/ADVISORIES...
AR...None.
LA...None.
OK...None.
TX...None.
&&

19/33/15
Hazardous weather outlook, May 17, 12:46 PM CDT, 1 hour 10 minutes before
Hazardous Weather Outlook
National Weather Service Shreveport LA
1246 PM CDT Mon May 17 2021

ARZ050-051-059>061-070>073-LAZ001>006-010>014-017>022-OKZ077-
TXZ096-097-108>112-124>126-136>138-149>153-165>167-181100-
Sevier-Howard-Little River-Hempstead-Nevada-Miller-Lafayette-
Columbia-Union-Caddo-Bossier-Webster-Claiborne-Lincoln-De Soto-
Red River-Bienville-Jackson-Ouachita-Sabine-Natchitoches-Winn-
Grant-Caldwell-La Salle-McCurtain-Bowie-Franklin-Titus-Camp-
Morris-Cass-Wood-Upshur-Marion-Smith-Gregg-Harrison-Cherokee-Rusk-
Panola-Nacogdoches-Shelby-Angelina-San Augustine-
1246 PM CDT Mon May 17 2021

This Hazardous Weather Outlook is for portions of south central
Arkansas, southwest Arkansas, north central Louisiana, northwest
Louisiana, southeast Oklahoma, east Texas and northeast Texas.

.DAY ONE...This Afternoon and Tonight...

Showers and thunderstorms will increase across the region today,
ahead of an upper level disturbance that will move through the
area. Isolated strong to severe thunderstorms can not be ruled
out, with damaging winds, hail, and brief heavy rainfall possible.
These showers and thunderstorms will diminish this evening with
the departure of this disturbance.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday...

Showers and thunderstorms will again return to the region Tuesday
in advance of an upper level storm system that will progress
through the Southern Rockies and into West Texas and the Oklahoma
Panhandle by midweek. The threat for locally heavy rainfall and
flash flooding will increase Tuesday night and Wednesday across
East Texas, Southeast Oklahoma, portions of Southwest Arkansas and
possibly Western Louisiana, as a complex of showers and
thunderstorms moves into these areas. Some of these storms may
also become severe during the late afternoon through the evening
hours Tuesday, before the heavy rain and flash flood threat
increases across these areas Tuesday night and Wednesday.
Widespread rainfall amounts of three to five inches are expected
this week across these areas this week, with isolated higher
amounts in excess of eight inches possible, especially over East
Texas. This rainfall will result in new rises and possible
flooding on area creeks and bayous, rivers and lakes. This
unsettled weather pattern will continue Thursday and Friday,
before gradually diminishing from east to west this weekend.

.SPOTTER INFORMATION STATEMENT...

Activation of emergency management personnel...amateur radio
operators...and storm spotters may be needed today across portions
of the region.

09

In the hours before

Local storm report, May 17, 11:18 AM CDT, 2 hours 38 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SHREVEPORT LA
1118 AM CDT MON MAY 17 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1017 AM     FLASH FLOOD      PINELAND                31.25N 93.97W
05/17/2021                   SABINE             TX   BROADCAST MEDIA

            SOME ROADS AND AREAS IN SABINE COUNTY ARE
            EXPERIENCING FLOODING: HIGHWAY 87 S
            YELLOWPINE AREA 96 IN BROOKELAND HIGHWAY 21
            TO NACOGDOCHES ANGELINA RIVER.

&&

25
Special weather statement, May 17, 12:13 PM CDT, 1 hour 43 minutes before
Special Weather Statement
National Weather Service Shreveport LA
1213 PM CDT Mon May 17 2021

LAZ001-010-017-TXZ151>153-166-171800-
De Soto LA-Caddo LA-Sabine LA-Panola TX-Nacogdoches TX-
San Augustine TX-Shelby TX-
1213 PM CDT Mon May 17 2021

...SIGNIFICANT WEATHER ADVISORY FOR DE SOTO...SOUTHWESTERN CADDO AND
NORTHWESTERN SABINE PARISHES...SOUTHEASTERN PANOLA...EAST CENTRAL
NACOGDOCHES...SHELBY AND NORTHERN SAN AUGUSTINE COUNTIES UNTIL 100 PM
CDT...

At 1213 PM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from 6 miles south of Deberry to 8 miles northwest
of Joaquin to near Tenaha to 6 miles northeast of Martinsville to
Melrose. Movement was east at 25 mph.

Winds in excess of 40 mph will be possible with these storms.

Locations impacted include...
Center, Mansfield, San Augustine, Stonewall, Logansport, Tenaha,
Joaquin, Melrose, Patroon, Martinsville, Bland Lake, Neuville,
Shelbyville, Chireno, Huxley, South Mansfield, Keachi, Grand Cane,
Longstreet and Stanley.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

These storms may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 3154 9457 3169 9438 3189 9424 3206 9419
      3227 9426 3230 9374 3201 9364 3185 9369
      3165 9383 3160 9389 3157 9398 3152 9398
      3144 9408
TIME...MOT...LOC 1713Z 275DEG 21KT 3220 9420 3206 9414 3189 9420 3169
9433 3159 9446

13
Special weather statement, May 17, 1:02 PM CDT, 54 minutes before
Special Weather Statement
National Weather Service Shreveport LA
102 PM CDT Mon May 17 2021

LAZ001-002-010>012-017-018-TXZ153-166-167-171845-
De Soto LA-Bossier LA-Bienville LA-Natchitoches LA-Red River LA-
Caddo LA-Sabine LA-Sabine TX-San Augustine TX-Shelby TX-
102 PM CDT Mon May 17 2021

...SIGNIFICANT WEATHER ADVISORY FOR EASTERN DE SOTO...RED RIVER...
WEST CENTRAL NATCHITOCHES...SOUTHEASTERN CADDO...SOUTHWESTERN
BIENVILLE...SOUTHEASTERN BOSSIER AND SABINE PARISHES...SOUTHEASTERN
SHELBY...EAST CENTRAL SAN AUGUSTINE AND SABINE COUNTIES UNTIL 145 PM
CDT...

At 102 PM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from 7 miles northeast of Stonewall to 6 miles
northwest of Converse to 8 miles southeast of Patroon to 6 miles
southeast of Macune. Movement was east at 35 mph.

Wind gusts up to 50 mph will be possible with these storms.

Locations impacted include...
Shreveport, Mansfield, Milam, Many, Coushatta, Zwolle, Ringgold,
Hemphill, Converse, Rosevine, Oak Grove, Pleasant Hill, Florien,
Martin, Huxley, South Mansfield, Hall Summit, Noble, Fisher and
Edgefield.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

These storms may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 3129 9418 3153 9395 3182 9383 3239 9372
      3242 9344 3241 9324 3243 9324 3244 9317
      3181 9329 3152 9339 3122 9368
TIME...MOT...LOC 1802Z 274DEG 30KT 3232 9371 3182 9380 3154 9392 3135
9410

13

The office that day

Everything else NWS Shreveport, LA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 16, 8:47 PM CDTRiver Flood WarningSHVFranklin, Morris, Red River, Titus20 days
May 16, 8:48 PM CDTRiver Flood WarningSHVWood7 days
May 16, 8:50 PM CDTRiver Flood WarningSHVFranklin, Morris, Titus21 days
May 17, 4:34 AM CDTAreal Flood AdvisorySHVSabine, San Augustine4 hr
May 17, 8:49 AM CDTRiver Flood WarningSHVGregg6 days
May 17, 8:54 AM CDTRiver Flood WarningSHVCass, Marion13 days
May 17, 8:56 AM CDTRiver Flood WarningSHVGregg, Harrison, Marion, Upshur10 days
May 17, 11:13 AM CDTAreal Flood WarningSHVAngelina, Nacogdoches, Sabine, San Augustine, Shelby6 hr
May 17, 12:13 PM CDTSpecial Weather StatementSHVShelby47 min
May 17, 1:02 PM CDTSpecial Weather StatementSHVSabine43 min
May 17, 2:10 PM CDTRiver Flood WarningSHVPanola, Shelby5 days
May 17, 9:06 AM CDTRiver Flood WarningSHVBienville, Bossier, Red River, Webster29 hr
May 17, 1:59 PM CDTSpecial Weather StatementSHVBienville, Natchitoches, Winn61 min
May 17, 2:55 PM CDTSpecial Weather StatementSHVGrant, Winn65 min

Nearby

Flash Flood Watches in Texas, 2021Flash Flood Watches in Louisiana, 2021Flash Flood Watches in Arkansas, 2021Every flash flood watch in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.